WO2020250366A1

WO2020250366A1 - Station installation assistance design device, station installation assistance design method, and program

Info

Publication number: WO2020250366A1
Application number: PCT/JP2019/023413
Authority: WO
Inventors: 一光坂元; 鈴木　賢司; 陽平片山; 洋輔藤野; 浩之福本
Original assignee: 日本電信電話株式会社
Priority date: 2019-06-13
Filing date: 2019-06-13
Publication date: 2020-12-17
Also published as: US20220240100A1; JP7223236B2; US12063520B2; JPWO2020250366A1

Abstract

This station installation design assistance device divides a service provision area into a plurality of areas, and performs station installation design in parallel for the plurality of areas. The station installation design assistance device comprises: an area dividing unit that divides the entire service provision area into the plurality of areas; a station installation priority order determination unit that determines, for each of the plurality of areas, the station installation priority order of station installation candidate locations present in the given area; and a station installation priority order adjustment unit that adjusts, on the basis of the degree of overlap between cells formed by installing a base station at each of the station installation candidate locations of each area, the station installation priority order determined by the station installation priority order determination unit.

Description

Station placement support design device, station placement support design method, and program

The present invention relates to a station placement support design device, a station placement support design method, and a program.

With the development of IoT (Internet of Things) technology, things with various sensors and communication functions (hereinafter referred to as "IoT devices" or "terminals") are connected to the network to collect remote data and IoT devices. Remote control of IoT is becoming more and more popular every year. Further, in recent years, LPWA (Low Power Wide Area network) has been attracting attention as a wireless communication method for IoT devices. LPWA includes, for example, LoRaWAN and Sigfox that use an unlicensed band (frequency band that does not require a radio station license), and LTE-M (Long Term Evolution for Machines) that uses a license band (frequency band that does not require a radio station license). ) And NB (Narrow Band) -IoT and other wireless communication methods.

IoT devices are often fixedly installed and used mainly in specific locations. On the other hand, radio wave propagation is highly location-dependent. As a result, if the IoT device is installed in a dead zone where the received power of radio waves from the base station is low, communication may be disabled for a long period of time. Therefore, it is important to design the station so that sufficient received power can be secured at the planned installation location of the IoT device.

In addition, if the number of terminals accommodated in the base station is too large, or if there is a lot of radio wave interference from interference sources such as nearby base stations, sufficient communication quality cannot be ensured even if a new IoT device is installed. There is. In this case, communication failures will occur frequently. Therefore, whether or not new IoT devices can be accommodated is determined by considering not only the evaluation of the received power at the planned installation location as described above, but also the usage status of the radio resources of the base station and the occurrence status of radio wave interference in the vicinity. It is important to judge in advance. Then, in order to make the determination, a means for estimating the communication success rate is required.

In a wireless communication system in which terminals are fixedly installed, desired wave reception power, interference signal power, traffic patterns, and base stations and terminals calculated from information indicating the base station installation location and terminal installation location. The communication success rate at each terminal can be estimated based on the information such as the thermal noise power in the above. The above traffic patterns include, for example, the frequency of uplink communication from the terminal to the base station, the communication time per uplink communication, and the communication time of an ACK (Acknowledge) signal from the base station to the terminal. Is included.

Conventionally, there are constraint conditions such as a condition of securing a capacity that can meet the demand for communication traffic, and optimization conditions such as a condition that the entire service provision area is covered by a minimum number of base stations. (See, for example, Patent Document 1 and Patent Document 2), a technique for designing a station so as to satisfy each of the above is disclosed.

The conventional station station design technology as disclosed in Patent Document 1 and Patent Document 2 and the like exerts the maximum effect when the station station design is performed collectively for the entire service providing area. However, according to such prior art, 3D (three-dimensional) map data, data indicating candidate station locations, and data on existing base stations in the entire service provision area, which is generally vast in general. It is necessary to calculate the station design after importing a large amount of data such as. Therefore, a huge amount of computational resources are required.

Note that the 3D map data includes information such as the altitude of each point, the height of the building, and the classification of land use. In addition, the data on the existing base station includes data on the base station to be installed at the station location selected by the station design.

As mentioned above, a huge amount of calculation resources are required when the station design is performed collectively for the entire service provision area. Therefore, in general, the entire service providing area may be divided into a plurality of areas, and station design may be performed individually for each of the divided plurality of areas. Then, in this case, in order to improve the processing efficiency, the station design for each of the divided plurality of areas may be performed in parallel.

In general, for the purpose of ensuring the accuracy of the station placement design at the end of the divided area, various types of areas expanded in the form of including the target area of the station placement design (for example, in the north, south, east, and west directions). After the data is imported, the station design is performed.

Japanese Unexamined Patent Publication No. 2001-285923 Japanese Patent No. 5538286

By dividing the entire service providing area into a plurality of areas in this way, the amount of data imported by the station design device in one station design is reduced. As a result, the computational resources required for one station design can be reduced. However, on the other hand, since the station placement design is performed independently and in parallel for each of the divided areas, base stations installed in different areas are configured at the boundary of the divided areas. Overlapping of cells may occur. Therefore, there is a problem that the area covered by the base station is wasted.

FIG. 6 is a diagram for explaining the problem in the case where the station placement design is performed in parallel for each of the plurality of divided areas described above. For example, as shown in FIG. 6, a case where the service providing area is divided into nine areas and the station placement design is performed will be described below. In FIG. 6, the quadrangle serving as the outer frame represents the range of the entire service providing area. In addition, the service provision area is divided into nine areas in a mesh pattern. As shown in FIG. 6, the nine areas are assigned area numbers (areas 1 to 9) that identify each area.

Further, in FIG. 6, the circles drawn by the dotted lines represent cells composed of base stations whose stationing priorities are indicated. In addition, the circle drawn by the solid line represents the candidate site for stationing. In addition, the number described in the balloon represents the station placement priority given to the station placement candidate site pointed to by the balloon.

Here, for example, it is assumed that the station placement design is performed so as to select the station placement candidate sites for the areas 4, the area 5, and the area 6, respectively. The station placement design shall be performed so as to satisfy the optimization conditions such as the condition of minimizing the number of base stations. Further, as a result of the station placement design, it is assumed that the station placement priority is determined as shown in FIG. In addition, in FIG. 6, the station placement priority is shown up to the first place for the area 4, and up to the second place for the area 5 and the area 6.

As described above, the station placement priority is determined so as to satisfy the optimization conditions for each divided area. Therefore, as shown in FIG. 6, for example, when focusing only on the area 5, the station candidate site having the first station priority and the station candidate site having the second station priority. By installing base stations in each of the above, the overlap of cells composed of both base stations is reduced. As a result, it can be seen that the area within the area is efficiently covered.

On the other hand, when focusing on both areas 4 and 5, if base stations are installed at candidate sites with the highest stationing priority in each area, both bases are as shown in FIG. The stations will be adjacent. Therefore, the cells configured by both base stations are often overlapped, and the area covered by the base stations is wasted.

Similarly, when focusing on both areas 5 and 6, if base stations are installed at candidate sites with the highest stationing priority in each area, both will be shown as shown in FIG. The base stations are not adjacent and the cells composed of both base stations do not overlap. However, next, if base stations are installed at the candidate sites for station placement having the second highest station placement priority in each area, both base stations will be adjacent to each other as shown in FIG. Therefore, the cells configured by both base stations are often overlapped, and the area covered by the base stations is wasted.

As described above, in the prior art, cells composed of base stations installed in both areas may overlap at the boundary of the divided areas. As a result, there is a problem that the area covered by the base station is wasted.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a technique capable of selecting a station location of a base station capable of efficiently covering an area.

One aspect of the present invention is a station station design support device that divides a service providing area into a plurality of areas and performs station station design in parallel for the plurality of areas, and the entire service providing area is divided into the plurality of areas. The area division section to be divided, the station placement priority determination section that determines the station placement priority of the station placement candidate sites existing in each of the plurality of areas, and the base station at the station placement candidate site in each area, respectively. A stationing design including a stationing priority adjusting unit that adjusts the stationing priority determined by the stationing priority determining unit based on the degree of overlap between cells formed by the installation. It is a support device.

According to the present invention, it is possible to select a station location of a base station that can efficiently cover the area.

It is a block diagram which shows the functional structure of the station design support apparatus 1 which concerns on one Embodiment of this invention. It is a figure for demonstrating the adjustment process of the station placement priority by the station placement design support device 1 which concerns on one Embodiment of this invention. It is a figure which shows the station placement priority before the adjustment process by the station placement priority adjustment unit 13 which concerns on one Embodiment of this invention is performed. It is a figure which shows the station placement priority after the adjustment process by the station placement priority adjustment unit 13 which concerns on one Embodiment of this invention is performed. It is a flowchart which shows the operation of the station design support apparatus 1 which concerns on one Embodiment of this invention. It is a figure for demonstrating the problem in the case where the station design is performed in parallel for each of a plurality of divided areas.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[Functional configuration of station design support device]
FIG. 1 is a block diagram showing a functional configuration of a station design support device 1 according to an embodiment of the present invention. As shown in FIG. 1, the station placement design support device 1 includes an area division unit 11, a station placement priority determination unit 12-1 to 12-N, a station placement priority adjustment unit 13, and a station placement location selection unit. 14 and.

The area division unit 11 acquires various data related to the entire service providing area, which is the target of the station design. The area division unit 11 may be configured to acquire the data from an external device or the like, or is stored in advance in a storage medium (not shown) included in the self-stationary design support device 1. It may be configured to acquire data.

The storage medium is, for example, a storage medium such as RAM (Random Access Memory; readable / writable memory), flash memory, EEPROM (Electrically Erasable Programmable Read Only Memory), HDD (Hard Disk Drive), or a storage medium thereof. Consists of any combination of.

The area division unit 11 divides the entire service provision area, which is the target of the station design, into N areas (areas 1 to N). The number of areas (value of N) is specified and the area number for identifying the divided area is assigned by, for example, a user who designs the station. The area division unit 11 allocates N divided areas (areas 1 to N) to the station placement priority determination units 12-1 to 12-N, respectively.

The area division unit 11 provides information indicating the area numbers corresponding to the areas assigned to the station placement priority determination units 12-1 to 12-N, respectively, to the station placement priority determination units 12-1 to 12-N. Output to each.

The method of dividing the area is not particularly limited. For example, the area may be divided so that the area of each area is equal, and the number of candidate station sites included in each area is substantially equal. It may be divided so as to be.

The station priority order determination units 12-1 to 12-N acquire the information indicating the area number output from the area division unit 11, respectively. The station placement priority determination units 12-1 to 12-N each perform station placement design with the area corresponding to the acquired area number as the target area.

The station priority priority determination units 12-1 to 12-N acquire various data related to the area corresponding to the acquired area number. The station placement priority determination units 12-1 to 12-N may be configured to acquire the data from an external device or the like, or may be a storage medium included in the station placement design support device 1 (shown in the figure). It may be configured to acquire the data stored in advance in (1). Alternatively, the station placement priority determination units 12-1 to 12-N may be configured to acquire the data via the area division unit 11.

Based on various acquired data, the station placement priority determination units 12-1 to 12-N each station placement priority for each station placement candidate site existing in the area corresponding to the acquired area number. To determine. The station placement priority determination units 12-1 to 12-N output information indicating the determined station placement priority to the station placement priority adjustment unit 13.

In a wireless communication system in which a terminal is fixedly installed, it is important that the station placement design is performed so that sufficient reception power and communication success rate can be secured at the place where the terminal is installed. Therefore, for example, it is desirable that the priority is set so that the higher the number of terminals whose received power and communication success rate are equal to or higher than a predetermined threshold value, the higher the priority is set. In the present embodiment, the higher the priority is set, the larger the number of terminals whose received power and communication success rate are equal to or higher than a predetermined threshold value.

Note that, for the station placement design for each area, the conventional station placement design techniques described in Patent Document 1 and Patent Document 2 and the like may be used.

In the present embodiment, when determining the station placement priority of the station placement candidate site in the area, the target area of the station placement design is ensured so that the accuracy of the station placement design at the end of the divided area is ensured. It is assumed that the station placement design is performed after various data about the expanded area in the form of including (for example, in the north, south, east, and west directions) are imported.

The station placement priority adjustment unit 13 provides information indicating the station placement priority of the station placement candidate sites in each area determined by the station placement priority determination units 12-1 to 12-N, respectively. Obtained from 12-1 to 12-N, respectively. In addition, the station placement priority adjustment unit 13 acquires various data regarding the entire service providing area that is the target of the station placement design.

The station placement priority adjustment unit 13 may be configured to acquire the data from an external device or the like, or is stored in advance in a storage medium (not shown) included in its own station placement design support device 1. It may be configured to acquire the relevant data. Alternatively, the station placement priority adjustment unit 13 may be configured to acquire the data via the station placement priority determination units 12-1 to 12-N.

Based on the acquired information, the station placement priority adjustment unit 13 calculates the degree of overlap between cells formed by installing base stations at each station placement candidate site in each area. The station placement priority adjustment unit 13 adjusts the station placement priority based on the calculated degree of cell overlap. The details of the specific adjustment process of the station placement priority will be described later. The station placement priority adjustment unit 13 outputs information indicating the station placement priority of each candidate site for station placement in each area after adjustment to the station placement location selection unit 14.

The station placement location selection unit 14 acquires the information output from the station placement priority adjustment unit 13 indicating the station placement priority of each candidate site for station placement in each area. Based on the acquired information, the station placement location selection unit 14 selects the highest priority station placement candidate site in each area as the base station placement location.

[Adjustment process of stationing priority]
Hereinafter, the stationing priority adjustment process will be described.
FIG. 2 is a diagram for explaining a station placement priority adjustment process by the station placement design support device 1 according to the embodiment of the present invention.

As shown in FIG. 2, the adjustment of the station placement priority according to the present embodiment is taken as an example of selecting the station location of the base station accommodating the terminals existing near the boundary between the area 1 and the area 2. The processing will be described.

In FIG. 2, the circles drawn by the dotted lines represent cells composed of base stations whose stationing priorities are indicated. In addition, the shaded circles drawn with solid lines represent the candidate sites for stationing. A circle drawn with a solid line and not shaded represents a terminal. In addition, the number described in the balloon represents the station placement priority given to the station placement candidate site pointed to by the balloon.

In order to simplify the figure and facilitate the explanation, in FIG. 2, in both

areas

1 and 2, there are two candidate sites for station placement (candidate sites for station placement # 1 and candidate sites for station placement # 2). Only illustrated.

As shown in FIG. 2, the number of terminals that can be accommodated (hereinafter referred to as "the number of accommodated terminals") when stationed in the station candidate site # 1 in area 1 is 13. The accommodating terminal is, for example, a terminal whose received power and communication success rate are equal to or higher than a predetermined threshold value. In addition, the number of accommodated terminals is three when the station is stationed at the station candidate site # 2 in the area 1. In addition, the number of accommodated terminals is 10 when the station is stationed at the station candidate site # 1 in the area 2. In addition, the number of accommodated terminals is eight when the station is stationed at the station candidate site # 2 in the area 2.

Further, FIG. 3 is a diagram showing the station placement priority of the station placement candidate site before the station placement priority adjustment process is performed by the station placement priority adjustment unit 13. As shown in FIG. 3, the candidate sites for stationing are prioritized in descending order of the number of accommodated terminals for each area (each area 1 and each area 2).

As described above, in both area 1 and area 2, the number of accommodated terminals is the largest when the base station is installed in the candidate station location # 1 (as described above, the number of terminals is 13 in area 1, which is the area. In 2, it will be 10 units). However, as shown in FIG. 2, terminals # 1 to terminal # 4 are two cells, a cell composed of base stations installed in area 1 and a cell composed of base stations installed in area 2. It is included in all of. Therefore, the overlapping range of cells in which these terminals # 1 to # 4 exist is a useless area.

Therefore, the station placement priority adjustment unit 13 first installs the number of accommodated terminals when the base station is installed in the station placement candidate site # 1 in the area 1 and the base station in the station placement candidate site # 1 in the area 2. Compare with the number of accommodated terminals in the case of. Then, the station placement priority adjustment unit 13 sets the area with the larger number of accommodated terminals as a reference area (hereinafter, referred to as "reference area"). In the example shown in FIG. 2, as described above, the number of accommodated terminals when stationed in the candidate station # 1 in area 1 is 13, and the stations are stationed in the candidate site # 1 in area 2. In this case, the number of accommodated terminals is 10, so area 1 is the reference area.

The station placement priority adjustment unit 13 is a terminal that corresponds to the above-mentioned overlapping portion (that is, exists in a range where cells overlap) from the number of accommodated terminals when a base station is installed in the station placement candidate site # 1 in area 2. Subtract the number of terminals. As described above, since the number of terminals corresponding to the overlapping portion is 4, the number of accommodated terminals when stationed at the station candidate site # 1 in area 2 is 6 by subtracting 4 from 10. It becomes a stand.

On the other hand, the number of accommodated terminals is 8 when a base station is installed in the candidate station location # 1 in area 2. Therefore, in area 2, the base station is set in the station candidate site # 2 by the above subtraction process, rather than the number of accommodated terminals (6) when the base station is installed in the station candidate site # 1. In this case, the number of accommodated terminals (8) is larger.

In this case, the station placement priority adjustment unit 13 replaces the station placement priority according to the number of accommodated terminals updated by considering the overlapping portion. FIG. 4 is a diagram showing the station placement priority after the adjustment process is performed by the station placement priority adjustment unit 13. Here, it is assumed that the number of accommodated terminals is less than 6 when a base station is installed in another candidate site for station placement (not shown) in Area 2.

In this way, by the station placement priority adjustment process by the station placement priority adjustment unit 13, the station placement priority in the area 1 is that the first place is the station placement candidate site # 1 and the second place is the station placement candidate site. It remains # 2. On the other hand, the station placement priority in the area 2 is adjusted so that the first place is the station placement candidate site # 2 and the second place is the station placement candidate site # 1.

By adjusting the stationing priority by the stationing priority adjusting unit 13, it is possible to reduce the waste caused by the overlapping of cells formed by the base stations installed in different areas at the boundary of the divided areas. Can be done. As a result, the service provision area is divided into a plurality of areas, and efficient station placement design is performed even when the station placement design is performed in parallel and independently for the divided plurality of areas. Will be possible.

In the above example, the range in which the received power is sufficient when the base station is installed in the candidate site is represented by a cell, and the communication success rate of all the terminals located in the cell is equal to or higher than the threshold value. It is said. However, in reality, the communication success rate may be low even when sufficient received power can be secured, depending on the degree of influence of cell-to-cell interference from surrounding cells.

In the above example, the number of accommodated terminals is used as an index showing the degree of overlap between cells composed of base stations installed in adjacent areas. However, the index indicating the degree of cell overlap is not limited to this, and the area of the area where the cells overlap may be used instead. In this case, the station placement priority determination units 12-1 to 12-N determine the station placement priority based on the area of the area where the cells overlap.

[Operation of station design support device]
Hereinafter, an example of the operation of the station design support device 1 will be described.
FIG. 5 is a flowchart showing the operation of the station design support device 1 according to the embodiment of the present invention.

The area division unit 11 divides the entire service providing area, which is the target of the station placement design, into N areas (areas 1 to N) (step S1). The area division unit 11 allocates the divided N areas to the station placement priority determination units 12-1 to 12-N, respectively.

The station placement priority determination units 12-1 to 12-N determine the station placement priority for each candidate site for station placement existing in the area assigned by the area division unit 11 (step S2).

The station placement priority adjustment unit 13 sets the station placement priority of the station placement candidate sites in each area determined by the station placement priority determination units 12-1 to 12-N, respectively, to the station placement candidate sites in each area. The adjustment is made based on the degree of overlap between the cells formed by the installation of the base station in (step S3).

The station placement location selection unit 14 has the highest priority station placement candidate site in each area based on the station placement priority of each station placement candidate site in each area adjusted by the station placement priority adjustment unit 13. Are selected as the location of each base station (step S4).
This completes the operation of the station design support device 1 shown in the flowchart of FIG.

As described above, the station station design support device 1 according to the embodiment of the present invention divides the service providing area into a plurality of areas, and performs station station design in parallel for the plurality of areas. The station placement design support device 1 determines the area division unit 11 that divides the entire service providing area into the plurality of areas, and the station placement priority of the station placement candidate sites existing in the area for each of the plurality of areas. The station placement priority determination is based on the degree of overlap between the station placement priority determination units 12-1 to 12-N and the cells formed by installing base stations at the station placement candidate sites in each area. A station placement priority adjustment unit 13 for adjusting the station placement priority determined by units 12-1 to 12-N is provided.

By providing the above configuration, the station design support device 1 according to the embodiment of the present invention divides the service providing area of the communication service by the wireless communication system, and parallels each of the divided plurality of areas. In the case of station placement design, the station placement priority of the station placement candidate sites determined for each of a plurality of areas is set, and the degree of overlap between cells formed by installing base stations at each station placement candidate site. Can be adjusted based on.

The adjustment is performed, for example, so that the number of terminals that can be accommodated is increased or the area of the area where cells overlap is smaller. As a result, the station design support device 1 can efficiently cover the area by selecting the adjusted station candidate site having the highest station placement priority as the base station station location. You can select the location of the station.

The station design support device 1 in the above-described embodiment can also be realized by a computer and a program. In this case, the program may be configured to be recorded on a recording medium or provided via a network.

The station design support device 1 in the above-described embodiment may be realized by a computer. In that case, the program for realizing this function may be recorded on a computer-readable recording medium, and the program recorded on the recording medium may be read by the computer system and executed. The term "computer system" as used herein includes hardware such as an OS and peripheral devices. Further, the "computer-readable recording medium" refers to a portable medium such as a flexible disk, a magneto-optical disk, a ROM, or a CD-ROM, or a storage device such as a hard disk built in a computer system. Further, a "computer-readable recording medium" is a communication line for transmitting a program via a network such as the Internet or a communication line such as a telephone line, and dynamically holds the program for a short period of time. It may also include a program that holds a program for a certain period of time, such as a volatile memory inside a computer system that serves as a server or a client in that case. Further, the above program may be for realizing a part of the above-mentioned functions, and may be for realizing the above-mentioned functions in combination with a program already recorded in the computer system. It may be realized by using a programmable logic device such as FPGA (Field Programmable Gate Array).

Although the embodiments of the present invention have been described above with reference to the drawings, it is clear that the above embodiments are merely examples of the present invention and the present invention is not limited to the above embodiments. Therefore, components may be added, omitted, replaced, and other changes may be made without departing from the technical idea and gist of the present invention.

1 ... Station design support device, 11 ... Area division unit, 12-1 to 12-N ... Station placement priority determination unit, 13 ... Station placement priority adjustment unit, 14 ... Station location selection department

Claims

It is a station station design support device that divides the service provision area into a plurality of areas and performs station station design in parallel for the plurality of areas.
An area division unit that divides the entire service providing area into the plurality of areas,
For each of the plurality of areas, a station placement priority determination unit that determines the station placement priority of the station placement candidate sites existing in the area, and a station placement priority determination unit.
Based on the degree of overlap between cells formed by installing base stations at candidate sites for stationing in each area, the stationing priority determined by the stationing priority determination unit is adjusted. Station priority adjustment department and
Station design support device equipped with.
In the station placement priority adjusted by the station placement priority adjustment unit, the station placement location selection unit that selects the highest priority station placement candidate site as the base station placement location for each of the areas is further added. The station design support device according to claim 1.
The station placement priority adjustment unit
The station design support device according to claim 1 or 2, wherein the number of accommodated terminals or the area of the area where the cells overlap is used as an index indicating the degree of overlap between the cells.
This is a station station design support method in which a service providing area is divided into a plurality of areas and station station design is performed in parallel for the plurality of areas.
An area division step that divides the entire service providing area into the plurality of areas, and
For each of the plurality of areas, a station placement priority determination step for determining the station placement priority of the station placement candidate sites existing in the area, and a station placement priority determination step.
A stationing priority adjustment step for adjusting the stationing priority based on the degree of overlap between cells formed by installing base stations at candidate sites for stationing in each area, and a stationing priority adjustment step.
A station design support method characterized by having.
A program for operating a computer as a station design support device according to any one of claims 1 to 3.